Treatment of neurological diseases with medications is often suboptimal due to the difficulty of medications to pass the blood brain barrier or BBB. Generally, the blood brain barrier only allows small, non-charged, or lipophilic molecules to cross. Therefore, only a minute fraction of the blood proteins are able to pass the blood brain barrier. Only about 0.01% to 0.50% of immunoglobulin G or IgG, with a molecular weight of 150 KD crosses the blood brain barrier. Accordingly, treatments with IgG targeting the central nervous system or CNS are not likely to be effective.
Generally, oral or parenteral administered medications require larger doses to achieve the desired effects than the same medications administered intrathecally. The intrathecal administration of medications may also significantly reduce side effects associated with larger oral or parenteral administered doses. Also substantial cost savings may be achieved by the significantly reduced dose required when administered intrathecally.
The customary way of accessing the cerebrospinal fluid is by performing a spinal tap or lumbar puncture. However, spinal taps generally cannot be done on a regular basis due to the associated discomfort, risk of infection, and frequent development of spinal fluid leak causing disabling headache. Medications have also been administered intrathecally, generally with an implanted pump. One such medication is baclofen used as a relaxant of skeletal muscle especially in treating spasticity. A baclofen pump is sold by Medtronic. The Medtronic baclofen pump is a programmable battery operated medical device that stores medication and is surgically placed in the abdomen and delivers the medication through a catheter inserted near the spine. These pumps are generally relatively large and cumbersome. They also generally produce a bulge from under the skin which is undesirable. The pumps are generally relatively expensive and are meant to continuously deliver non-biological materials. Additionally, the catheter use therewith is too thin for delivery of biological contents, such as proteins and cells, and the rolling pump mechanism delivering the medication has the risk of destroying the tertiary structure of proteins, which is essential to their function and could lyse cells. The pumps are generally very costly and need to be replaced every few years and require external communication with a computer system to assure proper functioning.
There have been efforts made to deliver medications with implanted devices or to the central nervous system. An implantable pump is disclosed in U.S. Pat. No. 7,927,325 entitled “Implantable Pump Connector for Catheter Attachment” issuing to Bright et al on Apr. 19, 2011. Another implanted drug delivery device is disclosed in U.S. Pat. No. 7,741,273 entitled “Drug Depot Implant Designs” issuing to McKay on Jun. 22, 2010. Another medication delivery method is disclosed in U.S. Pat. No. 7,629,311 entitled “Method to Facilitate Transmission of Large Molecules Across the Blood-Brain, Blood-Eye, and Blood-Nerve Barriers” issuing to Tobinick on Dec. 8, 2009. Therein disclosed is a method for delivering a biologic by administering parenterally into the perispinal space without direct intrathecal injection. Another device for administering a medication to the central nervous system is disclosed in U.S. Pat. No. 7,431,717 entitled “Central Nervous System Administration of Medications by Means of Pelvic Venous Catheterization and Reversal of Baton's Plexus” issuing to Gonzales on Oct. 7, 2008.
While these prior methods and devices have advanced the delivery of medications in a beneficial way they have not always delivered the medication as easily and efficiently as desired. Therefore, there is a need for a simple device that can easily provide medications to be delivered intrathecally without use of an implanted pump or repeated spinal taps.
Also, it is often difficult administering immunoglobulin therapy and complications have often arisen. Immunoglobulin therapy is commonly administered intravenously. As a result, usually relatively high doses of immunoglobulin are needed for treatment. This results in intravenous immunoglobulin therapy (IVIG) being relatively expensive. There are often adverse reactions associated with intravenous immunoglobulin (IVIG) therapy. An especially problematic and serious adverse side effect is aseptic meningitis. Aseptic meningitis is an acute inflammation of the meninges, or protective membranes covering the brain and spinal cord. As a result, it is generally believed by medical doctors in the field that intrathecal administering of immunoglobulin should not be done because of concerns about adverse reactions related to aseptic meningitis. That is, to introduce immunoglobulin intrathecally directly to the meninges in the subarachnoid space will likely increase adverse reactions including increased risk of aseptic meningitis.
Therefore there is the need for an improved method of providing immunoglobulin therapy that reduces the quantity of immunoglobulins previously administered intravenously and that is safe and effective.